Pharmacological approaches to chronic spinal cord injury.

Although research on neural tissue repair has made enormous progress in recent years, spinal cord injury remains a devastating condition for which there is still no cure. In fact, recent estimates of prevalence in the United States reveal that spinal cord injury has undergone a five-fold increase in the last decades. Though, it has become the second most common neurological problem in North America after Alzheimer's disease.

Functional and physiological effects of treadmill training induced by buspirone, carbidopa, and L-DOPA in clenbuterol-treated paraplegic mice.

Background: Chronic spinal cord injury may be complicated by weight loss, muscle atrophy, and bone loss.

Objective: The authors identified a combination pharmacotherapy using buspirone, carbidopa, and L-DOPA (BCD) that elicits bouts of locomotor-like movements in spinal cord-transected (Tx) mice. They then evaluated the effects of 8 weeks of treadmill training in Tx mice that received BCD or BCD + clenbuterol, a monoaminergic agent with anabolic properties, on locomotor function, muscle atrophy, adipose tissue loss, and bone density measures.

Effects of co-administration of clenbuterol and testosterone propionate on skeletal muscle in paraplegic mice.

Spinal cord injury (SCI) is generally associated with a rapid and significant decrease in muscle mass and corresponding changes in skeletal muscle properties. Although beta(2)-adrenergic and androgen receptor agonists are anabolic substances clearly shown to prevent or reverse muscle wasting in some pathological conditions, their effects in SCI patients remain largely unknown. Here we studied the effects of clenbuterol and testosterone propionate administered separately or in combination on skeletal muscle properties and adipose tissue in adult CD1 mice spinal-cord-transected (Tx) at the low-thoracic level (i.

Non-assisted treadmill training does not improve motor recovery and body composition in spinal cord-transected mice.

Study Design: Experiments in a mouse model of complete paraplegia.

Objectives: To evaluate the effect of non-assisted treadmill training on motor recovery and body composition in completely spinal cord-transected mice.

Settings: Laval University Medical Center, Neuroscience Unit, Quebec City, Quebec, Canada.

Recovery of locomotor function with combinatory drug treatments designed to synergistically activate specific neuronal networks.

Spinal cord injury (SCI) is a devastating condition generally leading to a permanent and irreversible loss of sensory and motor functions. We have identified recently a number of serotonergic, adrenergic and dopaminergic receptor agonists or precursors that can acutely elicit some motor and locomotor-like movements in completely spinal cord-transected (thoracic level) animals. However, only partial central network-activating effects were found with single molecules since none administered separately could elicit weight-bearing and functional stepping movements in Tx animals.

Key central pattern generators of the spinal cord.

In the central nervous system (CNS), central pattern generators (CPGs) are generally considered as specialized networks that can produce oscillatory motor output in the absence of any oscillatory input. For instance, respiration and mastication are among the critical biological functions well known to be controlled by such specialized networks. Several other CPGs have also been found specifically in the spinal cord.

Can the spinal cord learn and remember?

Learning and memory traditionally have been associated with cellular processes occurring in a specialized region of the brain called the hippocampus. However, recent data have provided strong evidence to suggest that comparable processes are also expressed in the spinal cord. Experiments performed mainly in spinal cord-transected animals have reported that, indeed, spinal-mediated functions, such as the stretch or flexion reflex, pain signaling, micturition, or locomotion, may undergo plasticity changes associated with partial functional recovery that occur spontaneously or conditionally.

A technological platform to optimize combinatorial treatment design and discovery for chronic spinal cord injury.

Chronic spinal cord injury (SCI) is associated with the development of serious medical concerns. In fact, it is increasingly well documented that most SCI patients who survive the first 24 hr will rapidly develop, within a few months to a few years, cardiovascular problems, type II diabetes, muscle wasting, osteoporosis, immune deficiencies, and other life-threatening problems. The cellular mechanisms underlying these so-called secondary health complications remain unclear, and no drug or standard approach has been developed to specifically treat these complications.

Plasticity in sublesionally located neurons following spinal cord injury.

Neuronal plasticity has been traditionally associated with learning and memory processes in the hippocampal regions of the brain. It is now generally accepted that plasticity phenomena are also associated with other kinds of cellular changes and modifications occurring in all areas of the CNS after injury or intense neuronal activity. For instance, spinal cord injuries have been associated with a series of cellular modifications and adaptations taking place distally in sublesional areas.

Spontaneous recovery of hindlimb movement in completely spinal cord transected mice: a comparison of assessment methods and conditions.

Study Design: To compare results obtained with a variety of locomotor rating scales in Th9/10 spinal cord transected (Tx) mice.

Objectives: To assess spontaneous recovery with a variety of rating scales to find the most sensitive methods for assessing recovery levels in Tx mice and differences associated with gender and condition.

Setting: Laval University Medical Center, Neuroscience Unit & Laval University, Department of Anatomy and Physiology, Quebec City, Quebec, Canada.

Vitamin A concentration in umbilical cord blood of infants from three separate regions of the province of Québec (Canada).

Background: Inuit women from Northern Québec have been shown to consume inadequate quantities of vitamin A. This study was conducted to evaluate the prevalence of blood vitamin A deficiency in newborns from 3 distinct populations of the province of Québec.

Methods: 594 newborns were included in this study (375 Inuit newborns from northern Québec (Nunavik), 107 Caucasian and Native newborns from the Lower Northern Shore of the Saint-Lawrence River (LNS) and 112 newborns from Southern Québec where clinical vitamin A deficiency is uncommon).

Time trends of persistent organic pollutants and heavy metals in umbilical cord blood of Inuit infants born in Nunavik (Québec, Canada) between 1994 and 2001.

Inuit inhabitants of Nunavik (northern Québec, Canada) consume great quantities of marine food and are therefore exposed to high doses of food chain contaminants. In this study, we report the time trends of persistent organic pollutants, mercury, and lead in umbilical cord blood of infants from three communities of the east coast of Hudson Bay in Nunavik. We analyzed 251 cord blood samples collected from 1994 through 2001 for polychlorinated biphenyls (PCBs), dichlorodiphenyl trichloroethane (DDT), dichlorodiphenyl dichloroethylene (DDE), hexachlorobenzene (HCB), chlordanes, lead, and mercury.

Crystal structure of human dehydroepiandrosterone sulphotransferase in complex with substrate.

Dehydroepiandrosterone sulphotransferase (DHEA-ST) is an enzyme that converts dehydroepiandrosterone (DHEA), and some other steroids, into their sulphonated forms. The enzyme catalyses the sulphonation of DHEA on the 3alpha-oxygen, with 3'-phosphoadenosine-5'-phosphosulphate contributing the sulphate. The structure of human DHEA-ST in complex with its preferred substrate DHEA has been solved here to 1.